Detroit Diesel — Lapping Injector Parts
Repair & overhaul · Fuel injector sealing surfaces
From a Detroit Diesel service manual — check it applies to your exact model before use.
Procedure
- Clean lapping blocks J 22090 with compressed air.
- Spread 600 grit dry lapping powder on one block.
- Place part flat on block and move in figure eight motion with light pressure.
- Clean and inspect part after each four or five passes.
- Wash part in clean solvent and dry with compressed air.
- Move part lightly on second block with lapping powder.
- Move part on third dry block in figure eight motion for mirror finish.
- Wash all lapped parts in clean solvent and dry.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 600 grit lapping powder
Source: Detroit Diesel service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.